Powering a 50A 220V outdoor swimspa

Hello,
I am running 220V about 100ft underground to power a swimspa (integral GFCI). I plan to run #6 underground rated wires. Two hots, neutral and a ground. I plan to use 1 inch PVC (rated for underground) buried about 16-18 inches deep. The trench does not run under driveways, sidewalks etc. There will be two 45 deg bends plus a 90 degree where the conduit rises out of the ground just outside the breaker panel.
My current panel has a 100A main breaker, a 30A breaker for a dryer - not used.
Question 1. Can I substitute a 50A 220V breaker for the 30A current dryer breaker - disconnecting it from the laundry? If not, can I increase the main breaker to say 120 or 150A. ( At some point in the future I'm replacing my 220V electric range with a gas range. Currently there is a 40A breaker connected to the electric range. )
Question 2. Any advice on my plan for running the wiring underground etc.? e.g. should I assemble the full 100ft and pull the wires with a snake or pull part way breaking at one of the 45's?
thanks very much,
Bob

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Powering a 50A 220V outdoor swimspa

Quote:

Originally Posted by firisland1

Hello,
I am running 220V about 100ft underground to power a swimspa (integral GFCI). I plan to run #6 underground rated wires. Two hots, neutral and a ground. I plan to use 1 inch PVC (rated for underground) buried about 16-18 inches deep. The trench does not run under driveways, sidewalks etc. There will be two 45 deg bends plus a 90 degree where the conduit rises out of the ground just outside the breaker panel.
My current panel has a 100A main breaker, a 30A breaker for a dryer - not used.
Question 1. Can I substitute a 50A 220V breaker for the 30A current dryer breaker - disconnecting it from the laundry? If not, can I increase the main breaker to say 120 or 150A. ( At some point in the future I'm replacing my 220V electric range with a gas range. Currently there is a 40A breaker connected to the electric range. )
Question 2. Any advice on my plan for running the wiring underground etc.? e.g. should I assemble the full 100ft and pull the wires with a snake or pull part way breaking at one of the 45's?
thanks very much,
Bob

Question 2. I would pipe it the whole way and push a snake through the pipe to bring the wires in. But if your using 1" PVC you are only allowed to install 3 # 6's in 1" PVC. So your pull might be a little hard you should make it easier for yourself and up to code and increase the pipe size to 1 1/4" PVC

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Powering a 50A 220V outdoor swimspa

Quote:

Originally Posted by dSilanskas

Question 2. I would pipe it the whole way and push a snake through the pipe to bring the wires in. But if your using 1" PVC you are only allowed to install 3 # 6's in 1" PVC. So your pull might be a little hard you should make it easier for yourself and up to code and increase the pipe size to 1 1/4" PVC

Where did you get this information? 3 #6's in 1" PVC? I don't see why 1" PVC would not be acceptable for this application. If the pulling the wire is in any way difficult, get some pulling lubricant for the wires. Just to be sure, your'e using the gray electrical PVC, not the white plumbing PVC.

Powering a 50A 220V outdoor swimspa

Question 2. I would pipe it the whole way and push a snake through the pipe to bring the wires in. But if your using 1" PVC you are only allowed to install 3 # 6's in 1" PVC. So your pull might be a little hard you should make it easier for yourself and up to code and increase the pipe size to 1 1/4" PVC

I see .0507 for a 6 gage thhn. And .314 for 1" ENT @ 40%. Even if you run size the ground the same and run it as # 6, I get a total of .2028

I agree 1.25" is a easier pull, but it does not appear to me that it is required.

Powering a 50A 220V outdoor swimspa

I never use 1-1/4" for a 50-60 amp spa circuit. I use 1", and I do a lot of spas.

__________________
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Answers based on the 2008 & 2011 NEC.

Powering a 50A 220V outdoor swimspa

Thanks to all for the great replies.
Regarding depth. Somewhere I'd read that if using underground rated GREY pvc and NOT under driveways as my run will be - that 12 inches depth was sufficient. Could someone please check this out ( I'm 16-17 inches down now and its REAL HARD ).
Bob

Powering a 50A 220V outdoor swimspa

Quote:

Originally Posted by firisland1

Thanks to all for the great replies.
Regarding depth. Somewhere I'd read that if using underground rated GREY pvc and NOT under driveways as my run will be - that 12 inches depth was sufficient. Could someone please check this out ( I'm 16-17 inches down now and its REAL HARD ).
Bob

The way I read it, it is 18".

NEC - 2005:

Section 680.20 Pools

Table 680.10 Minimum Burial Depths
Minimum Burial:

Nonmetallic raceways
listed for direct burial
without concrete
18"

IMC and RMC can be burried at a depth of 6" accourding to the same table. Both IMC and RMC are threaded thick walled metal conduit, IMC is lighter than RMC. RMC is very very heavy and very expensive. I have not noticed IMC at the big box stores. I am pretty sure it is RMC that they stock at most big box stores since that is what is used for masthead runs.